Cage is the primary equipment for carriers in a mine well. The bottom of the cage is connected with a tail rope beam suspension device. In the recent years, With the increase in security awareness and the continuously improvement of the automation level of the mine, the interior of the cage is equipped with some low voltage power devices, such as illumination lamps, electric cage curtain doors, secure communication devices and the like. Such apparatuses have to be supported by the stable and reliable power source to normally operate. In the prior art, one storage battery is employed to supply power; after the battery runs out, it must be removed for charging and replaced with a fully charged storage battery, or it is charged by utilizing a charging system disposed at a wellhead. This not only wastes human power, but also has long charging time and is likely to delay the normal operation of the lifting apparatus.